Black Obsidian

Black obsidian is a guardian stone, well-known for its protective capacity. It is worth bearing in mind, with this stone, that if you work with it a fair bit it will force negativity within the self to the surface, as well as mopping up any that it finds in the atmosphere. Its effects can be remarkably swift, and sometimes quite disruptive, so it's as well to have a couple of pieces of rose quartz about as well, just to balance things out a little. Black obsidian is particularly well suited for use in the kind of crystal gridding created to ward of negativity from outside specific sources.